Rio Tinto Investing $1.2 Billion to Modernize Quebec Hydropower Plant

Global mining giant Rio Tinto said it will invest $1.2 billion to modernize a hydroelectric power plant in Quebec, Canada. The company on May 15 said the project is part of its bid to secure future aluminum production in the Canadian province, even after the Trump administration imposed 25% tariffs on U.S. imports of aluminum and steel from Canada earlier this year.

The money will pay for upgrades to the 448-MW Isle-Maligne hydropower plant, which was commissioned in 1926 in Alma, Quebec. Officials said it represents Rio Tinto’s largest investment for the company’s hydro assets since at least the 1950s.

Rio Tinto, a mining and metals company headquartered in London, UK, said it wants to protect its aluminium production in the Saguenay-Lac-Saint-Jean region of Quebec for years to come. Officials said they want to ensure a reliable supply of renewable energy for the company’s smelters, casting houses, and other regional facilities. Rio Tinto said its aluminum smelters in the region are a production hub for aluminum cans, along with materials used in vehicles and military aircraft.

Rio Tinto’s aluminum exports to the U.S. were among the first targets of the Trump administration’s tariffs. Much of the aluminum imported by the U.S. comes from Canada.

Officials on Thursday said modernization of the Isle-Maligne plant will continue until 2032. The project includes replacing eight turbine-alternator groups, rehabilitating water intake and hydraulic passage, building an extension and mechanical workshop to the north of the power station, replacing electrical and mechanical equipment, and modifying a spillway so that it can be used reliably in winter.

“This major investment to modernize our facilities will ensure the long-term future and competitivity of our low carbon aluminium production in Quebec for decades to come for our Canadian and American customers,” said Sebastien Ross, Rio Tinto’s managing director for Atlantic operations, Sebastien Ross, in a statement. The company employs about 4,000 people in Quebec.

The project will run until 2032, and the company estimated that more than 300 people will work on the site at its peak. The investment includes replacing eight turbine-alternator groups, rehabilitating water intake and hydraulic passage, building an extension and mechanical workshop to the north of the power station, replacing electrical and mechanical equipment, and modifying a spillway so that it can be used reliably in winter. The new investment is in addition to other projects at the power plant included in a $183-million investment. That work calls for refurbishment of butterfly valves, and maintenance of two other turbine-alternator groups at Isle-Maligne.

Rio Tinto is among Canada’s largest private producers of hydropower. The company operates seven hydroelectric facilities, located in Quebec and British Columbia, that supply power for the company’s aluminum smelters. Another power station supplies hydroelectricity to Rio Tinto Iron Ore Co.’s port operations in Sept-Iles, Quebec.

Rio Tinto also began expanding its aluminum smelter in Saguenay, Quebec, in 2023 with the installation of 96 new pots using so-called AP60 low-carbon smelting technology at a cost of $1.1 billion.

The company has said it expects to invest about $4 billion in sustaining capital expenditures this year across all its global operations.

—Darrell Proctor is a senior editor for POWER.